If your goal is to identify the signals, I think the vertical with amp
(i.e. Might FIne Junk 1024 or even home-brew version) will do the job.
I suspect (but have no first hand knowledge) that noise sources will
not be very coherent, so they won't spike a spectrum analyser like a
real RF signal.

If you wanted to listen to the signal you identified, then I'd go for
the Wellbrook.